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A277258
Numbers such that n+R(n) | n*R(n), where R(n) is the digits reverse of n.
1
2, 4, 6, 8, 22, 44, 66, 88, 110, 132, 198, 202, 212, 220, 222, 231, 232, 242, 252, 262, 264, 272, 282, 292, 297, 330, 396, 404, 414, 424, 434, 440, 444, 454, 462, 464, 474, 484, 494, 495, 550, 594, 606, 616, 626, 636, 646, 656, 660, 666, 676, 686, 693, 696, 770
OFFSET
1,1
COMMENTS
This sequence contains all positive terms of A029951. So the sequence is infinite. - Altug Alkan, Oct 07 2016
LINKS
EXAMPLE
R(132) = 231, (132 * 231) / (132 + 231) = 30492 / 363 = 84.
MAPLE
R:=proc(w) local x, y, z; x:=w; y:=0; for z from 1 to ilog10(x)+1 do y:=10*y+(x mod 10); x:=trunc(x/10); od; y; end: P:= proc(q) local n; for n from 1 to q do if type(n*R(n)/(n+R(n)), integer) then print(n); fi; od; end: P(10^4);
MATHEMATICA
Select[Range@ 770, Function[r, Mod[# r, # + r] == 0]@ FromDigits@ Reverse@ IntegerDigits@ # &] (* Michael De Vlieger, Oct 14 2016 *)
PROG
(PARI) R(n) = eval(concat(Vecrev(Str(n))));
isok(n) = n*R(n) % (n+R(n)) == 0; \\ Michel Marcus, Oct 15 2016
CROSSREFS
KEYWORD
nonn,easy,base
AUTHOR
Paolo P. Lava, Oct 07 2016
STATUS
approved